As described in Japanese Patent Application Laid-Open No. 2003-189160, and Japanese Patent Application Laid-Open No. 2003-255428, a camera is often designed in such a manner as to perform auto exposure (AE) and auto focus (AF) when a shutter button is half pressed, and to perform image capturing when the shutter button is fully pressed.
However, a certain time is required in auto-focusing, because photometry and ranging are performed, and a lens is driven so as to focus a subject. As a result, even when a user fully presses the shutter button, the image capturing is not initiated until predetermined initialization such as the auto-focusing that is required for the image capturing is completed, and the image capturing cannot be performed at a user's intended timing in some case.